You sign the contract on Monday. Two weeks later, nothing visible has happened. Three weeks in, you start wondering if your Solar Partner has forgotten about you. The honest answer: residential solar projects take 8 to 16 weeks from signing to grid turn-on, and most of the work happens off your property. Here is what each of the five stages actually involves, where the real delays come from, and the specific points where silence stops being normal and becomes a red flag.
Stage 1: Site assessment and system design (week 1–3)
The first visible event is the site visit. Your Solar Partner sends an engineering team to measure your roof, photograph the electrical panel, evaluate shading patterns, and verify structural condition. The visit lasts one to two hours and produces the data the design team needs to finalize your layout.
If your roof needs a structural engineer's seal — common for steep pitches, older homes, or heavy snow loads — that review adds 3 to 14 days. The design team then finalizes panel layout, inverter placement, and electrical routing before placing equipment orders with suppliers.
You should receive a finished system design and timeline estimate by the end of week three. Expect an email confirming the panel layout, the inverter and racking models, the projected permit submission date, and the annual kWh production estimate for your address.
Red flag: no site visit scheduled by week two. Call your Solar Partner directly. This is the one stage where silence is unusual, because almost all the downstream work — permit application, equipment ordering, structural sign-off — depends on data the team can only collect on your roof.
Stage 2: Permitting is the biggest variable (week 2–8)
Permit review times swing more than any other factor in residential solar. Your Solar Partner submits the system design, electrical plans, and structural reports to your city or county building department, then waits for a reviewer to work through the queue.
Maricopa County, Arizona approves in 3 to 5 days. Colorado averages 2 to 3 weeks. Los Angeles and San Francisco Bay Area counties take 6 to 8 weeks. New York City and Chicago routinely run 10 to 12 weeks. Your jurisdiction is the single largest driver of your total project length.
If your home is in an HOA, the HOA review runs in parallel and adds 2 to 4 weeks. Your utility's interconnection application — a separate process from the building permit — also runs in parallel and takes another 5 days to 4 weeks depending on the utility.
Be skeptical of any Solar Partner who claims permits are not required for your jurisdiction. Every building code in the United States requires electrical and structural permits for rooftop solar. Skipping permits voids your homeowner's insurance coverage on the array and exposes you to enforcement action later.
Red flag: no permit number after six weeks. Ask for it directly, then check the status on your city or county permit portal. Most allow public lookup by property address.
Stage 3: Equipment delivery and installation (week 8–12)
Once your permit clears, the visible work begins quickly. Equipment is delivered and staged in your garage or yard a few days before the crew arrives. Installation itself takes one to three days for a standard 8 to 12 kWh-DC residential system.
Electricians run conduit and wiring from the panels to the inverter, mount the inverter and disconnect switch, tie a new circuit into your main panel, and install the monitoring gateway. Roof crews mount racking, lay flashing, and place panels. The roof work is loud. The garage work is mildly disruptive. Both typically finish within the same week.
When the crew leaves, your system is fully mounted and wired but not yet energized. It is not legal or safe to turn on a solar array before final building inspection and utility Permission to Operate. The disconnect switch stays open and the inverter stays off.
Do not ask your Solar Partner to power up the system early, even if they offer. Operating before Permission to Operate exposes both of you to liability, can void your homeowner's insurance coverage on the array, and risks backfeed into the grid during an outage.
Stage 4: Inspections and Permission to Operate (week 10–16)
Two approvals stand between completed installation and grid turn-on, and homeowners are usually unprepared for how long the second one takes.
First, your local building inspector verifies the installation meets code: panel mounting, conduit routing, wiring sizing, disconnect labeling, and the main panel tie-in. The visit takes 30 to 60 minutes. If something fails, your Solar Partner corrects the issue and requests a re-inspection within 3 to 7 days. Common failures are minor — disconnect placement, missing labels, conduit support. Inspector scheduling itself can add 2 to 4 weeks in busy jurisdictions.
Second, your utility issues a Permission to Operate (PTO) letter. This is the step most homeowners do not know exists. Even after the building inspection passes, your system cannot legally turn on until PTO arrives.
Some rural cooperatives issue PTO in 48 hours. PG&E and Southern California Edison typically take 2 to 4 weeks. Some large utilities run 4 to 8 weeks during high-volume seasons.
The delay is real engineering review, not paperwork. The utility verifies your inverter's anti-islanding protection meets their specifications so a grid outage cannot back-feed power into a line worker repairing a downed wire. That review is the legitimate reason the wait exists.
Red flag: no PTO update six weeks after passing your final inspection.
When silence becomes a red flag
Most of the 8 to 16 weeks is legitimate waiting. A few specific gaps, though, are signals to pick up the phone.
No site visit by week three means your Solar Partner is disorganized or oversold. Ask for a specific calendar date and an engineer's name.
No permit number by week six means you should ask for the application receipt and look up the status on your city or county portal yourself. If the application has not been filed, that is the issue to escalate.
No inspector appointment within three weeks of completed installation means ask your Solar Partner to expedite using their contractor scheduling priority. Most maintain direct relationships with building departments that homeowners cannot access.
No PTO update six weeks after passing inspection means ask for the utility's interconnection tracking number, then call the utility directly.
Be skeptical of any sales pitch promising two-week installation. Outside of fast-permit jurisdictions like Maricopa County, that promise usually means the Solar Partner is skipping permits or will miss the deadline. The right question to ask before signing: how long does permitting typically take in my specific jurisdiction? A specific number is the right answer.
Solrova's Solar Design Studio models the realistic project timeline for your address — including the permit speed for your county and the typical PTO window for your utility. You see the actual weeks before signing, not the sales promise. Open the Solar Design Studio.